Each custom consent link is LIVE and will generate submissions to the IRS. It is important to not submit fake requests that trigger the IRS to mark you as a bad actor.
To test your link(s), simply add "?test" to the end of each link and you'll see a Test mode bar at the top. Test mode allows you to enter information and gather consent without initiating a submission to the IRS.
Example: https://customconsent.app.tax?test